Hogg voted against Neville Chamberlain in the Norway Debate of May 1940, and supported Winston Churchill. He served briefly in the desert campaign as a platoon commander with the Rifle Brigade during World War II. His commanding officer had been his contemporary at Eton; after him and the second-in-command, Captain Hogg was the third-oldest officer in the battalion. After a knee wound in August 1941, which almost cost him his right leg, Hogg was deemed too old for further front-line service, and later served on the staff of General "Jumbo" Wilson before leaving the army with the rank of major. In the run-up to the 1945 election, Hogg wrote a response to the book Guilty Men, called The Left was never Right .
In June 1963 when his fellow Minister John Profumo had to resign after admitting telling lies to Parliament about his private life Lord Hailsham attacked him savagely on television. The following evening Profumo's brother-in-law, Lord Balfour of Inchrye Harold Balfour, 1st Baron Balfour of Inchrye remarked on live television that "When a man has by self-indulgence acquired the shape of Lord Hailsham sexual continence requires no more than a sense of the ridiculous".
He was Leader of the House of Lords when Harold Macmillan, the Prime Minister, announced his sudden resignation for health reasons at the start of the 1963 Conservative Party conference. At that time there was no formal ballot for the Conservative Party leadership. Lord Hailsham, who was at first Macmillan's preferred successor, announced that he would use the newly-enacted Peerage Act to disclaim his title and fight a by-election and return to the House of Commons. His publicity-seeking antics at the Party Conference (eg. feeding his newborn baby in public, and allowing his supporters to distribute "Q" (for Quintin) badges) were considered vulgar at the time, so in the end Macmillan did not encourage senior party members to choose Hogg as his successor.
Hogg failed to win the leadership bid but did win his father's old constituency of St Marylebone. He remarked to a journalist "After all, I am only 55. Perhaps about 1970 if there was a Tory government some ass might make me Lord Chancellor" - a remark which caused some amusement when in June 1970 there was a Conservative (also known as "Tory") government and Edward Heath did indeed make him Lord Chancellor.
Hogg as a campaigner was known for his robust rhetoric and theatrical gestures. He was usually in good form in dealing with hecklers, a valuable skill in the 1960s, and was prominent in the 1964 general election. At one point, when a Labour Party supporter waved a Harold Wilson placard in front of him, Hogg smacked it with his walking stick.
He served in the Conservative shadow cabinet during the Wilson government, and built up his practice at the Bar where one of his clients was the Prime Minister and his political opponent, Harold Wison. When Edward Heath won the 1970 general election he received a life peerage as Baron Hailsham of St Marylebone, of Herstmonceaux in the County of Sussex, and became Lord Chancellor. Hogg was the first to return to the House of Lords as a life peer after having disclaimed an hereditary peerage. Hailsham's choice of Lord Widgery as Lord Chief Justice was criticised by his opponents, although he later redeemed himself in the eyes of the profession by appointing Lord Lane to succeed Widgery.
Lord Hailsham of St Marylebone was appointed a Companion of Honour in 1975 and became a Knight of the Garter in 1988. On his death his title was inherited by his son Douglas Hogg. Due to the Labour government's House of Lords Act 1999, which removed the automatic link between hereditary peerages and the right to sit in the House of Lords, it was not necessary for the 3rd Viscount to disclaim his viscountcy to remain as a MP.
According to the book, the role of Conservatism is not to oppose all change but to resist and balance the volatility of current political fads and ideology, and to defend a middle position that enshrines a slowly-changing organic humane traditionalism.
For example, in the 19th-century, Conservatives opposed classic Liberalism, favouring factory regulation, market intervention, and various controls to mitigate the effects of laissez faire capitalism, but in the 20th-century, the role of Conservativism was to oppose a danger from the opposite direction, the excessive regulation, intervention, and controls favoured by Socialism.
The book was published as a companion to "Labour Marches On" by John Parker M.P.
Lord Hailsham was also known for his writings on faith and belief. In 1975 he published his spiritual autobiography The Door Wherein I Went, which included a brief chapter in Christian apologetics, using legal arguments concerning the evidences for the life of Christ. The book included a particularly moving passage about suicide; when he was a young man his half-brother had taken his own life and the experience left him with a deep conviction that suicide is always wrong. His writings on Christianity have been the subject of discussion in the writings of Ross Clifford. Lord Hailsham revisited themes of faith in his memoirs A Sparrow's Flight, and the book's title alluded to remarks about sparrows and faith recorded in Bede's Ecclesiastical History and the words of Christ in the Gospel of Matthew.
His children, all by his second wife, Mary Evelyn Martin, are: